Holstentor, Germany - A UNESCO World Heritage Site since 1987, this eye-catching structure is one of the relics of Lübeck's medieval city fortifications. Known for its cone-shaped towers and arched entrance, the Holstentor is a powerful symbol of the city.

Green Gate, Poland - Built from 1568 to 1571 as the formal residence of Poland's monarchs, the Green Gate is one of Gdańsk's most recognized buildings. It is situated between the city's Long Market (Długi Targ) and the River Motława.(Photo: Wikimedia/CC BY-SA 30 PL)

City Gates, Portugal - Located at Ponta Delgada on the Azores island of São Miguel, the iconic and ornate 18th-century Portas da Cidade used to overlook the old quay. The structure was transferred to Praça de Gonçalo Velho during construction of the city's seafront avenue.

Powder Tower, Czech Republic - One of the original 13 gates built in the late 15th century to enclose Prague's Old Town, this monumental structure was intended to be an attractive entrance to the city. However, during the 17th century it was used to store gunpowder, hence its present-day name.

Pile Gate, Croatia - The main entrance to Dubrovnik Old Town is accessed via a wooden drawbridge, which was once lifted every evening to prevent unwelcome guests from entering the medieval, walled city. These days visitors can walk under this imposing city gate, built in 1537, with no fear of being challenged.

Porta Nigra, Germany - The largest Roman city gate north of the Alps, the astonishing "Black Gate" in Trier, a city on the banks of the River Moselle, is designated as part of Trier's Roman Monuments UNESCO World Heritage Site. The gate dates back to 170 CE.

Qianmen archery tower, China - Otherwise known as Zhengyangmen, the archery tower is set within Beijing's historic city wall, and was built to guard the southern entry into the imperial city. What you see today is largely a 1914 reconstruction of the original 1419 structure.

The Lion Gate, Greece - This gate stood as the main entrance of the Bronze Age citadel of Mycenae. Built around 1250 BCE, it is the sole surviving monumental piece of Mycenaean sculpture. It's named after the limestone slab featuring confronting lionesses posing on both sides of a pillar above the lintel. (Photo: Flickr/CC BY 2.0)

Alcalá Gate, Spain - Originally one of the gates of the former Walls of Philip V that surrounded Madrid between 1625 and 1868, Puerta de Alcalá today stands as a Neo-classical monument in the city's Plaza de la Independencia.

Porte Cailhau, France - A cherished Bordeaux landmark, Porte Cailhau is the main entrance into medieval Bordeaux. Built in the 15th century to celebrate King Charles VII's victory at the Battle of Fornovo (1495) and conquest of the kingdom of Naples, this grandiose gatehouse is especially alluring when illuminated at night.

Buland Darwaza, India - Built in the early 17th century on the orders of the Mughal emperor Akbar, the "Gate of Victory" is the main entrance to the palace at Fatehpur Sikri, a town in the Agra District of Uttar Pradesh. (Photo: Wikimedia/CC BY-SA 3.0)

Golden Gate, Jerusalem - The only eastern gate of the Temple Mount—venerated as a holy site in Judaism, Christianity, and Islam alike—the Golden Gate was used exclusively by the High Priest and all those who aided him. It has been walled up since medieval times.

Arch of the New Gate, Portugal - The Arco da Porta Nova in Braga, a city in northern Portugal, serves as a triumphal arch which decorates the western entrance to the medieval wall of the Old Town. It was opened in 1512. (Photo: Wikimedia/CC BY-SA 3.0)

Brandenburg Gate, Germany - One of the most recognized monumental gates in the world, Berlin's Brandenburg Gate dates back to 1791. Miraculously surviving the Second World War, it stands today as not only as a symbol of the tumultuous history of Europe and Germany, but also of European peace and unity.

Namdaemun, South Korea - Officially known as the Sungnyemun, this grand gateway dates back to the 14th century and was one of eight that were embedded within the fortress wall that surrounded the city. A fire in 2008 destroyed the structure's wooden components. Fully restored, the gate was reopened in 2013.

Zijlpoort, Netherlands - Decorative Zijlpoort is a gate in the Dutch city of Leiden. Dating back to 1667, it's one of only three of the original eight gates that are still standing. Its name refers to the nearby river, the Zijl.

St Mary Gate, Spain - Burgos, in northern Spain, is the historic capital of Castile and known for its fine collection of historic monuments. Among them is the Arco de Santa María, a medieval gate set in the city's 14th-century walls.

Sheep Gate, Ireland - Seen here in early morning mist, Sheep Gate is the only surviving gate of five that once provided access to the town of Trim, in County Meath. It's believed to date back to at least 1290. (Photo: Wikimedia/CC BY-SA 4.0)

Serranos Gate, Spain - An imposing Valencia landmark and one of the best-preserved monuments in the city, this is one of the 12 gates that formed part of the ancient city wall. Built towards the end of the 14th century, the towers once served as a prison. (Photo: Wikimedia/CC BY-SA 4.0)

Porte St. Louis, Canada - One of four surviving gates that form part of the ramparts of Quebec City—the only remaining fortified city walls in North America north of Mexico—the foundations of Porte St. Louis date back to 1694. The fortifications are listed by UNESCO as a World Heritage Site. (Photo: Flickr/CC BY-SA 2.0)

Gateway of India, India - A Mumbai landmark, this monument was erected in 1911 to commemorate the landing of George V and Queen Mary. It was later used as a symbolic ceremonial entrance to India for Viceroys and the new Governors of Bombay. Today it's one of the city's top visitor attractions. (Photo: Wikimedia/CC BY-SA 2.0)

Notre Dame Gate, Malta - The Baroque Notre Dame Gate is the main gate of the Cottonera Lines, a 17th- and 18th-century network of fortifications built to form the outer defenses of the three Cities of Birgu, Senglea, and Cospicua.

Porta Camollia, Italy - Siena's medieval walls feature a number of portals including this one, which is located on via Camollia and opens into the city's Contrada of Istrice. The original gate, built during the 13th century, was razed during the 1555 siege of Siena. Visitors should look for the Medici heraldic shield with a stone arch, added to the rebuilt outer facade in 1604.

Porta Capuana, Italy - This ancient portal is all that remains of Naples' original city walls, razed in the 15th century. But it's not standing in its original location, which was much nearer to the city's Castel Capuano. The gateway was rebuilt and relocated to its present location in 1484!

Roosevelt Arch, USA - The symbolic gateway to the north entrance to Yellowstone National Park in Montana, Roosevelt Arch—named for Theodore Roosevelt, the 26th president of the United States—was completed in 1903 and was the the first major entrance for Yellowstone, itself the first national park in the US.

Once the principal ceremonial entrance to the City of London from Westminster, this 17th-century ornamental Baroque arched gateway designed by Christopher Wren now stands in Paternoster Square next to St Paul's Cathedral.

Where to admire the world's most iconic city gates

These monumental gateways are historic urban landmarks

Some of the most remarkable urban landmarks are city gates—a gate which is, or was, set within a wall and traditionally built to provide a point of controlled access to, and departure from, a walled city.

In times past everything and everyone, including people, goods, and animals, would pass beneath these imposing gateways. Vehicles, too, would enter and leave a walled city via these monumental transit points.

Depending on their historical context, city gates functioned as formidable defensive barriers. However, they also served other purposes. Taxes and tolls were collected at a city gate. They were commonly used to display all sorts of public information such as civic announcements, standards of local measures, and legal declarations. A city gate could also act as a medical post, where health checks were carried out to curb the spread of disease. And they provided a more grisly function, as a location for warning or intimidation when the decapitated heads of executed criminals, traitors, and other public enemies would be exhibited for all to see.

City gates are found across the world in cities dating back to antiquity to around the 19th century. Some are little more than ruins. Others still stand in magnificent grandeur, symbols of wealth and power from a bygone age.

Browse the gallery and take a look at some of the most celebrated city gates ever built.